Art of humidification



July 20,1926.

A. J. LOEPSINGER ART OF HUMIDIFICATION Filed Sept. 12, 1924 z F HA? x Z f 574-7? 1 1i 4- L9 /0 Y /7// HLBERTJ. LOEPSINGER iNVENTOR 5757/7 /2 ATTORNEYS Patented July 20, 1926.

UNITED STATES Application iuea September 13, in. "aerial Io. 731,4.

This invention relates to improvements in the art of humidification. More particularly it relates to the art of maintaining or raising the humidity of the atmospheric air in a room by blowing a jet of steam into the air. This very simple method of humidifying would probably be extensively in use were it not that condensation of heat as to raise an objectionable the steam gives out such .the temperature locally to extentan evil so serious that humidifying by steam jets is forbidden by law in some places. It is an object of the present invention to eliminate the objectionable features so that done by a jet of steam without sensible or undue increase of temperature of the room locally, where the steam is set free, due to its introduction and condensation.

This is accomplished by associating-a discharge of air expansively with the steam which air has previously been compressed and separated from the heat produced by its compression, so that when malized compressed air is liberated in connection with the steam the latent heat of condensation of the steam is immediately utilized to supply the heat demanded'by the expanding air and is absorbed thereby; The

invention may be carried out with apparatus of various-types, one suitable and simple ar-, rangementbeing the provision of a-nozzle, fed b a compressed air pipe and a steam pipe, y which the air and moisture are discharged so that both expand into the air of the room. Some other gas mi ht be, employed, instead of air, but air wi probably be found most'convenient for ordinary industrial uses. As a measure of preparation the air or whatever gas is to be used is compressed in any suitable compression apparatus. In such case a part ofthe work done by the compressing apparatus appears as heat, raising the temperature of the air and e surrounding container. This heat is to be rejected, so that the air the process is approximately at atmospheric temperature or lower; and theair is to be used in sufficient volume relative to the steam, so that the heat, which has been rejected and which must be reabsorbed when it expands to atmospheric pressure, approximately equals the heat which is set free by the steam in its condensation.

.ticles of. water in liquid form.

as heretofore practiced thehumidifying can be the de-ther- Y which is used in.

The condensation to which reference is thus made is that which occurs locally where the steam is released, producing the visible cloud or mist which is colloquially called steam, which consists of very small ar away it evaporates, assumin tlve humidity of the atmospi to absorb it, and this eva ere is such as ration requires As this Data. that thB relaheat, so that the net additlon of heat to the atmosphere by condensation of in'ected steam, and subtraction of heat from t e atmosphere by the re-evaporation of the may be supposed" to be theoretically But in past ex rience the injection of such steam has pro uced unbearable ditions, locally at least; and there has been undoubtedly an increment of heat due to equal.

the excess of. temperature of condensation .above, the temperature of'atmosphere which, accumulating through a period of time, makes a considerable aggregate addition of same,

living con-;

uantity of heat, to that already contained in t e room; and this accumulation, at certain times of the year and under certain atmospheric conditions is very objectionable. ,The process and apparatus of the invention provide for the avoidance or diminution of the local increase densation occurs, so that tem ratures are equalized around the room; an it may provide absolutel for the neutralization of the not heat actuafiy introduced by steam, so that in the aggregate result the ,total quantity of heat in. the room is not affected by the humidifying apparatus or process, but only humidity is added; and the chan oftemperature locally are so minimize of circulation of air and moisture, that no part of the roomis thereby rendered unduly igh or low in temperature.

These results. are accomplished by introducing cooled compressed air whose expansion to atmospheric pressure takes heat equal .to the quantity of heat which comes in with the steam as a n t quantity of sensible heat. The quantity in known, depending upon the temperature, pressure and qu 'ntity of steam, computation will show. what pressure and temperature and quantity of compressed air is requisite to absorb this heat by its expansion to atmospheric pressure and temperature. practice the provision for expansion of this of temperature where the con-,

, .with aid reduced by steam-being of vapor,.in this instance steam,

air in the midst of the steam, which also is expanded, will cause its heat to be taken initially from that liberated by the condensation of the steam as well as from that introduced by the high sensible heat of steam, but with the dissemination of the whole through the atmosphere of the room, with evaporation of the condensed steam, the excess of heat initially observed will disappear, becoming latent heat of vaporization at atmospheric temperature.

The accompanying drawings illustrate varieties of apparatus by which this proc ess can be practiced; and it will. be understood that other arrangements also can be made. It is intended that the patent shall cover by suitable expression in the appended claims whatever patentable features exist in the invention disclosed so far as the same relates to the process or method of distributing a gas, such as the vapor of water,

through a body of air such as the air of a room. i

In the accompan ing drawings:

Figure 1 is a si e elevation of a medial section through apparatus by which the invention may be practiced; and Figures 2, 3 and 4: are similar views showing modifications of apparatus.

Referring to the drawings, a duct 10, leading from a compressor (not shown) contains a dry gas at relatively low pressure, say 10 to 15 pounds gage, of the temerature of the local atmosphere. Into this ry gas which may be air, there is introduce through an inlet pipe 12, a current which upon intermingling with the relatively air is condensed into tiny floating articles of liquid. The resulting mixture of air and vapor particles issues through the discharge nozzle 14 into the atmosphere in the form of very fine fog.

The apparatus may be so designed and proportioned, with respect to the quantity of air and steam discharged, that the number of heat units, added, net, by introduction of the vapor will equal, very closely, the number of cat units acquired by the air in expanding from its compressed state in theduct to its normal state in the atmoshere. And such heat units as may remain in excess after the expansion is complete are taken up by the subsequent evaporation of the particles. Accordingly there is no increase in the local temperature, as has heretofore resulted when humidification has been efiected through the addition of steam to the atmosphere.

In Figure 1 the duct lg is shown as having a gradual contraction 10, followed by an enlargement constituting the discharge nozzle 14. The steam inlet pi e 12 is connected to the duct at the sma est part of the contraction or neck, 10, where the vecool dry locity of the air is greatest and its side pressure is most reduced, in accordance with the law utilized in the Venturi meter. In an antecedent enlargement 12 of this steam pipe there is a heating unit, represented as a coil 16 having electrical connections 18, and a supply of water surrounding the coil, being heated thereby to form the steam. The rapidly moving air current in the neck of the duct acts with a sort of aspirator effect to draw into itself the rising vaporand, by arranging the water supply close up to the neck, the aspiration efiect can be utilized to reduce the pressure on the water to below that of atmosphere, thus lowering the boiling point, with consequent saving of the electrical current required for heating. The increased velocity of the air also produces a desired projecting efiect which enables the fog to be driven well into the region to be humidified.

The contraction 10" of the air duct is not an essential feature. It may be omitted as shown in Figure 2, where the duct 10 is illustrated as continuing at uniform size past the steam inlet 12, to the expanding discharge nozzle 14. The latter also may be dispensed with, if desired, and the apparatus be provided in the form of Figure 3, in which the contraction or neck 10 is open to the atmosphere just beyond the junction with the steam inlet 12. Or an even more simple arrangement could be used in which, as shown in Figure 4, the contraction and nozzle are both absent and the discharge is from the open end of a uniform pipe, into which the steam is introduced just before the discharge opening is reached.

The steam may be rovided by any other convenient means, as y a gas ame, or by piping from an ordinary steam boiler, wit coal furnace.

1 claim as my invention:

.1. The art of humidification, comprising the introducing of steam into a current of compressed air whose heat of compression has been lost, which steam condenses; and projecting the mixture into the atmosphere, whereby the resulting free expansion of the compressed air absorbs heat introduced by the steam.

2. The art of humidification, comprising the com ressing of air, with loss of heat produced t ereby; injecting steam into said compressed air; and projecting the resulting mixture into the region to be humidified with freedom for expansion of the gas: whereby the sensible heat introduced and heat liberated by the condensation of the steam are absorbed by the expansion of the compressed air and evaporation of the condensed steam.

3. The art of humidification, comprising the compression of air with loss of heat produced thereby; moving said air toward the region to be humidified; introducing steam to the moving air while the latter is still compressed; and then liberating the mixture of air and steam into by the sensible heat of in the expansion of atmospheric pressure.

4. The art of humidification, comprising the introducing of steam into a stream of moving compressed air of temperature not greater than that of the atmosphere, and then projecting the mixed air and steam into the atmosphere whereby the expansion of the air absorbs some of the liberated latent heat of condensation of the steam.

5. The art of humidification comprising the discharge, into atmosphere and in the same vicinity, of steam, and of compressed air whose heat of compression has been lost, whereby the introduction, condensation and later evaporation into atmospheric humidity of the steam simultaneously with the expansion of the compressed air effects a transfer said steam is absorbed the compressed air to the atmosphere whereof heat units without increase of the atmospheric temperature.

6. The art of humidification comprising the discharge of steam and compressed air into atmosphere which is to be humidified, respectively in position to co-act on air in the same region, and severally at pressure, temperature and quantitative rate suflicient for the sensible heat introduced by the steam to be absorbed by the expansion of the air introduced, whereby approximately a constant temperature of air 15 maintained in the region.

7. The art of humidification wherein substantially the exact amount of heat liberated by the cooling of water introduced to the atmosphere as steam to supply humidity is withdrawn by the expanding of air introdueed. i

Signed at Boston, Massachusetts, this fourth day of August, 1924.

ALBERT J. LOEPSINGER. 

